WO2011001431A1

WO2011001431A1 - Personal tourniquet

Info

Publication number: WO2011001431A1
Application number: PCT/IL2010/000523
Authority: WO
Inventors: Eliram Azulay
Original assignee: Eshed H.A. Medical Device Ltd.
Priority date: 2009-06-29
Filing date: 2010-06-29
Publication date: 2011-01-06

Abstract

A tourniquet, comprising a rigid though pliable pressure applying unit retaining an inflatable bladder, the unit having two opposite ends, an inflation mechanism being in fluid communication with the bladder for inflating the bladder at a pre-determined flow rate, and a non-elastic adjustable tourniquet cuff arrangement for wrapping around a patient's limb.

Description

PERSONAL TOURNIQUET

FIELD OF THE INVENTION

This invention relates to tourniquets especially adapted for personal use.

BACKGROUND OF THE INVENTION

In medical emergency conditions it is often necessary to apply a tourniquet around a body limb to control the blood flow. The tourniquet is applied around a patient's limb and is then deployed into its operation position so as to apply a desired pressure on the limb or on the artery.

WO 91/18571 discloses a novel bandaging system for uses comprising serious lacerations, surgery, burns, and non-wound injuries. The system provides initial cooling and pressure at the wound site, compression and contraction of the wound, maintenance of optimum clotting temperature, maintenance of blood circulation, protection from contamination, and antihemorrhagic, anesthetic, and antiseptic agents applied to wound site in a disposable biomedical bandage. Comprising an inflatable bladder and pressure application aparatus the bandaging system is totally self-contained and inhibits body fluid loss while improving blood clotting time and permitting replenishment of blood supply to body parts distal to the heart beyond an intervening injury.

US 5,411,518 discloses an apparatus for wrapping around a body member to restrict the flow of blood. This apparatus includes a tourniquet having an inflatable plenum, and a pad for minimizing patient discomfort. The pad is positionable between the tourniquet and the body member, and it is fabricated from a substantially absorbent, wrinkle free material. A stiffener positioned within the inflatable plenum assures that the tourniquet applies a uniform pressure upon the body member to which it is applied. The stiffener is partially shape retaining for holding the tourniquet in a circular configuration. SUMMARY OF THE INVENTION

In accordance with one aspect of the present invention, there is provided a tourniquet, comprising:

(a) a rigid though pliable pressure applying unit retaining an inflatable bladder, said unit having two opposite ends;

(b) an inflation mechanism being in fluid communication with said bladder for inflating the bladder at a pre-determined flow rate; and

(c) a non-elastic adjustable tourniquet cuff arrangement for wrapping around a patient's limb;

Any one or more of the following features and designs may be included in the tourniquet according to the present invention:

^■ the non-elastic adjustable tourniquet cuff typically extends from one end of the pressure applying unit or of the inflation mechanism and is attached (fixedly or detachably) to an other end of the of the pressure applying unit or of the inflation mechanism.

^■ The pressure applying unit may be in a form of a pouch-like element comprising an internal flexible layer for applying over the limb, and an external non-elastic layer, giving rise to a space therebetween retaining therein the bladder. The external layer may also be flexible to the extent that it may assume the contour of the limb, however it will not deform/bulge under inflation pressure of the inflatable bladder. The external layer of the pressure applying unit may be made of a material such as PVC.

^■ The internal layer of the pressure applying unit may be made of a non-absorbent material such as Neoprene.

^■ The tourniquet may comprise a substantially rigid pressure element integrated with the internal layer, radially projecting (i.e. towards the limb when applied thereover) such that when the tourniquet is applied over the limb, local pressure is applied at a location of said pressure element, so as to apply concentrated pressure on the artery.

^■ The tourniquet may comprise a pressure control mechanism, e.g. a control valve, for maintaining pressure within the bladder within a predetermined range. ■ The inflation mechanism may comprise a release mechanism for controlled pressure release of fluid into the bladder, allowing thereby gradual increase of pressure within the bladder.

■ The inflation mechanism may further comprise a pressure control mechanism for controlling removal of fluid out of the bladder, allowing thereby gradual decrease of pressure therewithin, or instantaneous deflation.

■ The pressure control mechanism may comprise a pressure indicator indicative of pressure within the bladder, which may be visual and/or acoustic.

■ The pressure control mechanism may be adapted to control said release mechanism so as to allow an addition of the fluid to the bladder when the pressure therein falls behind the predetermined range.

■ The tourniquet may further comprise a time indicator activated in correspondence with initiation of the bladder expansion.

■ The fastening arrangement may comprise a hook and loop fastener.

^■ Some or all the parts of the tourniquet may be disposable.

The tourniquet according to the present invention is easy to operate and substantially does not require special training or skills to operate same. The overall operation time, i.e. applying the tourniquet over an individual's limb and activating the inflation mechanism so as to inflate the bladder into the operative state is short, may take less than 10 seconds.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to understand the invention and to see how it may be carried out in practice, embodiments will now be described, by way of non-limiting examples only, with reference to the accompanying drawings, in which:

Fig. IA is an isometric view of one example of a tourniquet according to the present invention;

Fig. IB is an isometric view of another example of a tourniquet according to the present invention;

Fig. 1C illustrates the tourniquet of Fig. IA when applied over an individual's limb;

Fig. 2 is a bottom view of a pressure applying unit constituting part of the tourniquet shown in Figs. IA to 1C; Figs. 3A and 3B are a side view and a cross-sectional side view, respectively, of the pressure applying unit shown in Fig. 2, showing an inflatable bladder in its deflated state;

Figs. 4A and 4B are a side view and a cross-sectional side view, respectively, of the pressure applying unit shown in Figs. 2, 3A and 3B, showing the inflatable bladder in its inflated state;

Fig. 5A is a bottom view of another example of a pressure applying unit according to the present invention;

Fig. 5B is a side view of the pressure applying unit shown in Fig. 5A, at its inflated state;

Fig. 5C is a bottom view of another example of a pressure applying unit according to the present invention;

Fig. 5D is a side view of the pressure applying unit shown in Fig. 5 C, at its inflated state;

Fig. 6A is a front cross-sectional view of one example of an inflation mechanism according to the present invention, suitable for use with the tourniquet, at its pre-activated position;

Fig. 6B is a front cross-sectional view of the inflation mechanism shown in Fig. 6A, at its activated position; and

Fig. 7 is a partial front view of another example of an inflation mechanism according to the present invention.

DETAILED DESCRIPTION OF EMBODIMENTS

Attention is first directed to Fig. IA of the drawings illustrating a tourniquet according to an embodiment of the present invention generally designated 10 comprising three principle components namely a pressure applying unit generally designated 12, a inflating mechanism generally designated 14 and an adjustable tourniquet cuff arrangement generally designated 16.

With further reference being made also to Figs. 2 to 4, the pressure applying component 12 is illustrated and is seem to comprise an external layer 20 made of a substantially rigid though pliable, however non-elastic external material such as PVC. Attached thereto on its inner surface there is an inner layer 22 typically made of a non- absorbent material such as Neoprene, said inner layer being typically elastic and being attached at its peripheral edges to corresponding edges of the external layer 20, constituting therebetween a space 24 (Figs. 3B and 4B are secured to one another by stitching, adhering, welding, etc..

The inflatable bladder 28 may be a resilient inflatable bladder or it may be a bladder of predetermined volume being formed between a deflated state (Fig. 3B) and an inflated state (Fig. 4B). The bladder 28 is in slow communication via appropriate aperture 32 formed in the pressure applying unit 12 with the inflation mechanism 14 for controlled inflation of the inflatable bladder 28.

Reverting to Fig. IA, the adjustable tourniquet cuff 16 is in the form of a non- elastible strap 36 e.g. made of Gorte-tex^®, fabric, etc. and is typically attached at one end thereof 38 to the inflation mechanism 14 and is fitted at its opposite end 42 with a buckle 44 with a length adjusting arrangement at 46, wherein said buckle 44 is fitted for articulation by a hook 48 integrated at another side of the inflation mechanism 14.

The inflation mechanism 14 is a rapid-type mechanism e.g. of the type disclosed in Figs. 6A and 6B comprising a gas cartridge 60 comprised within a housing 62, said housing fitted with a piercing plunger 64 and an activating lever 66 operation of which will be discussed hereinafter in further detail. It is noticed that the inflation mechanism 14 comprises a flow nozzle 68 which at the assembled position is tightly and sealingly received within inflation aperture 32 of the pressure applying component 12 and into the inflatable bladder 28.

The device 10 may be a disposable device or it may be a multiple use article wherein the inflation mechanism 14 requires replacement of a pressurized gas cartridge 60. For that purpose, the housing 62 is fitted at its lower end with a removable screw- coupled cover 70 through which the cartridge 60 may be removed and replaced by a fresh one.

The cartridge 60 is formed at its upper end with a sealing foil 74 extending opposite the piercing plunger 64, the latter coaxially extending above the gas cylinder 60, however below the axle 76 of the activating lever 66. As can be seen, the pivot end of the operating lever 66 is formed with a canned surface 78, whereby displacing the activating lever 66 in direction of arrow 80 entails downward displacement of the piercing plunger 64 into its piercing position, against the biasing effect of a coiled spring 82, into the position illustrated in Fig. 6B. In accordance with one particular example, the housing 62 is fitted at its flow nozzle 68 with a check valve 86 facilitating pressurized gas flow only in direction of arrow 88, i.e. into the inflatable bladder 28 however preventing gas leak in a reverse direction which would thus cause deflation of the inflatable bladder 28.

According to a modification of the inflation mechanism 14, as illustrated in Fig. 7 of the drawings, the gas cylinder 92 is inserted into the housing 94 and upon tightening of the cover 96 the cylinder 92 is spontaneously punctured by a fixedly projecting piercing plunger 98 however, pressurized gas contained within the cylinder 92 is prevented at this stage from flowing towards the inflatable bladder owing to a sealing valve arrangement (inventors, please provide appropriate drawing disclosing the above) extending between the outlet from the pressurized cylinder 92 towards the flow nozzle of the housing 94.

Turning now to Fig. 1C of the drawings, a tourniquet in accordance with the embodiment of Figs. 1 to 4 is illustrated placed over a limb schematically illustrated and designated 100. A central portion 104 of the pressure applying component (see Figs. 3 and 4) is placed over an artery of the limb 100 and the tourniquet cuff 36 is then wrapped around the limb 100 with the buckle 44 placed within the hook 48 for arresting thereby and thereupon the flack 108 of the strap is manually tensioned by the length adjusting arrangement 46 (e.g. a tile and hook fastener, etc.) to apply an initial fastening of the tourniquet 10 over the limb and to prevent unintentional disengagement thereof. Then, the activating lever 66 of the inflation mechanism 14 is displaced in direction of arrow 110 in Fig. 1C so as to discharge the pressurized gas from the pressurized cylinder 60 into the inflatable bladder 28 at a pre-determined flow rate, thereby applying direct pressure over the artery of the limb 100, thus substantially stopping blood flow therein. In particular, the applied pressure is at least 300 mmHg. During the inflation, the internal layer 22 is stretched by the inflated bladder 28, allowing an internal extension of the bladder 28 towards the limb 100, while the external layer 20 prevents the outward extension of the bladder 28. The process described above may take less than ten seconds.

With reference to Fig. IB, the cuff 16 may comprise a Velcro^® type fasteners 130 and 132, the first being fixed to the end 42 of the strap 36 and the second being fixed to the pressure applying component 12. Turning now to Figs. 5A and 5B illustrating a modification of the invention wherein the inner layer 122 of a pressure applying component 120 is fitted with a pressure concentration element in the form of a bar-like element 132 made of a substantially rigid material adapted to be placed over the location of an artery within the limb so as to concentrate pressure applied thereto upon inflation of the pressure applying component. As can be seen in Figs. 5A and 5B, the bar-like element 132 may substantially transverse the pressure applying component, i.e. extends substantially in alignment with the adjustable tourniquet cuff 16 so that at the operative state said element 132 thereby increasing tourniquation effect.. Alternatively, as shown in Figs. 5C and 5D, a bar-like element 142 may be substantially perpendicular to the tourniquet cuff 16, so that at the operative state the element 142 placed parallel to the artery to which the pressure is applied.

The inflation mechanism may comprise a release mechanism for controlling a release of the fluid from the fluid container into the bladder 28.

The inflation mechanism may further comprise a removal mechanism for controlling a removal of the fluid out of the bladder 28, so that the pressure within the bladder is gradually decreased. The removal mechanism may be an independent assembly or may constitute a part of the release mechanism. One example of such a mechanism may be found in a valve of Tycos DuraShock Sphygmomanometer manufactured by Welch Allyn, or other mechanisms used in the industry.

The tourniquet according to the present invention may comprise a pressure control mechanism for maintaining pressure within the bladder 28 within a predetermined range. Such a mechanism may comprise a pressure indicator of a pressure within the bladder, which may be visual, acoustic or may comprise any other indication means providing the user, in real time, the ability to determine whether the pressure within the bladder is sufficient. The pressure indicator may further comprise an alarm system for warning the user when the pressure reaches upper or lower thresholds of the predetermined pressure range, or when the pressure is already out of this range.

The tourniquet according to the present invention may comprise a time indicator for measuring time passed from the activation of the inflation device, i.e. the beginning of the bladder inflation. The time indicator may comprise a counter, such as a mechanical or phosphoric counter, adapted for forward and/or backward counting. The tourniquet according to the present invention may further comprise a visual indication, such as marking arrows or labels, of the way it has to be applied over the limb, i.e. positioning the internal layer 22 to face the limb, the bladder 28 to be as close as possible to the place of injury etc.

Those skilled in the art to which this invention pertains will readily appreciate that numerous changes, variations, and modifications can be made without departing from the scope of the invention, mutatis mutandis.

Claims

CLAIMS:

1. A tourniquet, comprising:

(c) a non-elastic adjustable tourniquet cuff arrangement for wrapping around a patient's limb.

2. A tourniquet according to Claim 1, wherein the pressure applying unit is a pouch-like element comprising an internal flexible layer for applying over the limb and an external non-elastic layer giving rise to a space therebetween retaining therein the bladder.

3. A tourniquet according to Claim 2, wherein the external layer is flexible.

4. A tourniquet according to any one of Claims 1 to 3, further comprising a substantially rigid pressure element radially projecting towards the limb such that when the tourniquet is applied over the limb, local pressure is applied at a location of said pressure element.

5. A tourniquet according to any one of Claims 1 to 4, further comprising pressure control mechanism for maintaining pressure within the bladder within a predetermined range.

6. A tourniquet according to any one of Claims 1 to 5, wherein the inflation mechanism comprises a release mechanism for controlling a release of fluid into the bladder, allowing thereby a gradual increase of pressure therewithin.

7. A tourniquet according to any one of Claims 1 to 6, wherein the inflation mechanism comprises a removal mechanism for controlling a removal of fluid out of the bladder, allowing thereby a gradual decrease of pressure therewithin.

8. A tourniquet according to any one of Claims 5 to 7, wherein said pressure control mechanism further comprises pressure indicator of the pressure within the bladder.

9. A tourniquet according to Claim 8, wherein said indicator is visual.

10. A tourniquet according to Claims 8 or 9, wherein said indicator is acoustic.

11. A tourniquet according to any one of Claims 6 to 10, wherein said pressure control mechanism is adapted to control said release mechanism so as to allow an addition of the fluid to the bladder when the pressure therein falls behind the predetermined range.

12. A tourniquet according to any one of Claims 1 to 11, further comprising a time indicator activated in correspondence with initiation of the bladder expansion.